Expression analysis of melatonin receptor subtypes in the ovary of domestic chicken.

Melatonin (N-acetyl-5-methoxytryptamine), an indole hormone, regulates various biological functions through three different receptor subtypes (Mel-1a, Mel-1b, and Mel-1c). However, the distribution of different melatonin receptor subtypes in chicken reproductive tissues was not known. In the present investigation, the partial sequences of ovarian melatonin receptor subtypes (Mel-1a, Mel-1b, and Mel-1c) were characterized. Further, the expression profile of melatonin receptor subtypes in the granulosa and theca layers of different preovulatory and postovulatory follicles (POF) were studied by semi-quantitative RT-PCR. The expression of all three subtypes of melatonin receptors were observed in the ovary of domestic chicken. Analysis of partial sequences of ovarian melatonin receptors revealed that the melatonin subtypes were identical to the brain receptors. In small white ovary follicles, we observed only the expression of mel-1b receptors, but not mel-1a or mel-1c receptors. In yellow follicles, all the three subtypes of receptors expression were noticed. Interestingly, we observed the expression of mel-1a receptor only in thecal layer, but not in granulosa layer. In contrast, mel-1b and -1c receptors were expressed in both granulosa and thecal layer. During the regression of POF, we observed significant upregulation of melatonin receptors (mel-1a and 1c) expression, that downregulated in the later stages of regression. We assume that the expression of melatonin receptors might have been influenced by the atresia or apoptosis of different follicular layers in POF. Our findings suggest that the differential distribution of melatonin receptor subtypes might have distinct downstream cellular functions in the ovarian tissues.

Immune responses induced by DNA vaccines encoding Newcastle virus haemagglutinin and/or fusion proteins in maternal antibody-positive commercial broiler chicken.

1. The immune responses induced by recombinant plasmids containing Newcastle disease virus (NDV) F (pVAX.nd.f) or HN (pcDNA.nd.hn) genes separately or in combination in bi-cistronic (pIRES.nd.hn.f) constructs were evaluated in maternal antibody-positive commercial chicks. 2. Immunofluorescence and immunoperoxidase tests demonstrated the expression of both F and HN proteins in Vero cells. Real-time PCR analysis revealed the expression of HN and/or F genes in muscle, peripheral blood mononuclear cells (PBMC), spleen and liver after immunisation. 3. Chicks inoculated intramuscularly thrice (two booster doses) with pVAX.nd.f and pcDNA.nd.hn did not develop detectable haemagglutination inhibiting (HI) antibodies. In contrast, an increase in a NDV-specific cell-mediated immune response was demonstrated. 4. After challenge with virulent NDV, chicks immunised with the recombinant plasmids as well as those in control groups succumbed to Newcastle disease. 5. Based on these results, it is concluded that DNA vaccines containing HN and/or F genes fail to protect commercial chicks, possibly due to interference from maternal antibodies.

A case report of melioidosis in a diabetic patient in a union territory.

Melioidosis is an emerging disease in India. Cases have also been reported from South East Asia, Australia and Japan. Major risk factors for melioidosis are diabetes mellitus, preexisting renal disease and thalassemia. Exposure to contaminated soil and water are also significant occupational hazards associated with the disease. A patient with diabetes of six years duration on regular medication presented with fever, generalised myalgia and headache for a week. Blood and bone marrow culture yielded Burkholderia pseudomallei. A Computed tomography (CT) study of the thorax also revealed multiple scattered nodules in both lungs. The patient was treated with imipenem and doxycycline. His condition improved gradually and he was advised oral sulfamethoxazole/trimethoprim and doxycycline for a period of three months and has been followed up regularly.